A memory device having a three-dimensional structure is proposed. In the memory device, memory holes are formed in a stacked body including a plurality of electrode layers. A charge storage film and a semiconductor film are provided in the memory hole to extend in a stacking direction of the stacked body.
The memory hole is formed by, for example, anisotropic dry etching. As the aspect ratio of the memory hole increases, it becomes difficult to control the diameter of the memory hole so as to be uniform in the depth direction. The difference in the diameter of the memory hole may lead to a variation in the characteristics of memory cells.